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SE/30 Xceed greyscale adapter cloning thread

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As long as we don’t know the internals of the ASIC there’s not much more to be done.

 

@maceffects how do those guys in china go about reverse engineering complex custom ICs like the one on that card? Expose the die and map out the chip layout under a microscope?

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1 hour ago, Bolle said:

As long as we don’t know the internals of the ASIC there’s not much more to be done.

 

@maceffects how do those guys in china go about reverse engineering complex custom ICs like the one on that card? Expose the die and map out the chip layout under a microscope?

I’m not really sure but I know it’s not cheap. Actually I think $600-$800 per chip. 

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4 hours ago, CC_333 said:

But only *AFTER* a working clone of the card gets created first!* Only THEN can extra features be considered.

I'm making the point that it might not even be POSSIBLE to clone the EXCEED without substituting an available RAMDAC of far superior performance. We'd be tying down floating signals redundant to the internal grayscale, function, using only I/O required. The additionaal function is held in reserve for future development of the Alpha platform. I find it had to imagine a RAMDAC so limited as that on the EXCEED is an available part.

 

IOW, we likely won't find available parts crappy enough to slavishly recreate the card in its over 30 year old form. VRAM/Video Memory types currently availability is another source of curiosity for me. @trag what do you think about parts availability issues?

 

I'd say implement for the least (internal gs only) while making choices along the way intended to support the most, whatever that's determined to be during the course of pulling off step one.

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8 hours ago, maceffects said:

I’m not really sure but I know it’s not cheap. Actually I think $600-$800 per chip

That’s actually way less than I thought.

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FPGAs can take over everything the main chip did, as long as you know the logic behind it. using SDRAM coupled to the FPGA would work fine for the video speeds this thing is working at. 

 

 

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19 hours ago, Trash80toHP_Mini said:

I'm making the point that it might not even be POSSIBLE to clone the EXCEED without substituting an available RAMDAC of far superior performance. We'd be tying down floating signals redundant to the internal grayscale, function, using only I/O required. The additionaal function is held in reserve for future development of the Alpha platform. I find it had to imagine a RAMDAC so limited as that on the EXCEED is an available part.

Right, OK. I should've been more specific in that I meant *functional* clone; in other words, not one that necessarily uses the exact same components (that would be unrealistic!), but one which mimics the original's functionality using modern components.

 

This, then, would allow all the functionality to be reproduced, and then, via a firmware update or something, more advanced features can be added (like the Floppy Emu, where BMoW added HD20 functionality simply by updating the firmware (though some very early models needed a hardware fix or two for it to work due to thier being a slightly different design, as I recall)).

 

c

Edited by CC_333

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Ignore this post, move to quote tag disaster corrected version below. [:I]

Quote

The Macintosh II Video Card is unaccelerated. With an optional RAM upgrade that requires eight 120ns DIP chips, it supports 640 x 480 in 8-bit color. Without the RAM upgrade, it supports 640 x 480 in 4-bit color. It will not drive the Apple 12″ RGB Display or 12″ Monochrome Display, which only operate at 512 x 384 resolution. It only supports 640 x 480 output.

Quote

 


 

B - the Internal GS XCEED card implements ability of the Macintosh II High Resolution Video Card to output that 512 x 384 res, but tweaked to match the 342 vertical line res of Compact Mac video.

LEM

 

 

 

 

 

 

Thankfully, that card's default setting is 512 x 384 which makes sense as coming up in 640x480 would be useless in the case of a system configured with the smaller display. I'm thinking the same must be true for the XCEED card defaulting to internal, no? So tweaking the Internal GS driver shouldn't be necessary for doing an internal only clone.

 

I've yet to find PAL formula listings for the Toby card, but believe they're out there on the web, if not somewhere in Apple's Developer series. I can't imagine that dumbing a Toby card down to run the SE/30 512x384 internal display would be much of a problem? As Toby constitutes the XCEED card's external monitor support function, adding external support identical to that of the XCEED would be easily enough done?

 

 

 

 
The Mac II High Res Video Card is unaccelerated. It supports resolutions of 640 x 480 and 512 x 384, which was the resolution of Apple’s 12″ color and monochrome displays. The video card was available in two configurations. The 4-bit model supports 16 color (4-bit) video on a 640 x 480 display, 256 colors (8-bit video) on a 512 x 384 display. The 8-bit model supports 8-bit/256-color video on a 640 x 480 display.
 
Edited by Trash80toHP_Mini

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5 hours ago, techknight said:

FPGAs can take over everything the main chip did, as long as you know the logic behind it. using SDRAM coupled to the FPGA would work fine for the video speeds this thing is working at. 

That's what I was thinking/hoping. As I try to get across below, the only thing about the EXCEED card that really requires cloning is its ability to sync with the A/B and substitution of its output to drive its proprietary neck board. The rest of it is A/B switching its output from internal grayscale resolution to its function as a mediocre VidCard driving an external display.

 

Much of the legwork has been done in dlv's project.

In a quick review of the topic I found Balrog's post: "https://archive.org/details/MicronXCeedTechDocs — you may have to click "Show All" under Download Options."


@Gorgonopsand I had a bit of a back and forth going about just about everything I barely understand and I'm grateful for his lessons. I dragged in a tangential discussion about developing for 030 PDS as a simpler approach than going straight to NuBus, which puts discussion there right smack into this thread. The most useful thing I brought up was probably using the Macintosh II Video Card (aka Toby) as a design example and pointing out the in depth documentation of it in the Designing Cards and Drivers for the Macintosh series.


I'm going to posit here:
A - the external only XCEED card is an 030 PDS implementation of the NuBus Toby card as its output is the same as the 640x480@8-bit Grayscale Card;
LEM

Quote

The Macintosh II Video Card is unaccelerated. With an optional RAM upgrade that requires eight 120ns DIP chips, it supports 640 x 480 in 8-bit color. Without the RAM upgrade, it supports 640 x 480 in 4-bit color. It will not drive the Apple 12″ RGB Display or 12″ Monochrome Display, which only operate at 512 x 384 resolution. It only supports 640 x 480 output.

B - the Internal GS XCEED card implements the ability of the Macintosh II High Resolution Video Card to output the 512 x 384 resolutions for driving the later Apple Displays that are missing from the TobyCard. But the XCEED version was tweaked to match the 342 vertical line resolution of Compact Mac video.
LEM

Quote

The Macintosh II High Res Video Card is unaccelerated. It supports resolutions of 640 x 480 and 512 x 384, which was the resolution of Apple’s 12″ color and monochrome displays. The video card was available in two configurations. The 4-bit model supports 16 color (4-bit) video on a 640 x 480 display, 256 colors (8-bit video) on a 512 x 384 display. The 8-bit model supports 8-bit/256-color video on a 640 x 480 display.


With an optional RAM upgrade, which requires eight 120ns DIP chips, the 4-bit version supports 640 x 480 in 8-bit color.

Thankfully, that card's default setting is 512 x384***** which makes sense as coming up in 640x480 would be useless in the case of a system configured with the smaller display. Im thinking the same must be true for the XCEED card defaulting to internal, no? So tweaking the Internal GS driver shouldn't be necessary for doing an internal only clone?


Schematic, driver and DECLROM info for Toby are in Apple's Developer Docs, but I've yet to find PAL formula listings for the Toby card. I believe they're out there on the web, if not somewhere in Apple's Developer series that I've yet to run across. I can't imagine that dumbing a Toby card down to run the SE/30 512x342 internal display would be an insurmountable problem? As Toby constitutes the XCEED card's external monitor support function, adding external support of the same spec, if not identical in implementation to that of the XCEED's would be easily enough done in phase 2?

 

 

**** Macintosh II High-Resolution Video Card: New Features

 

 

Edited by Trash80toHP_Mini

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I searched "xceed" in the MacUser archive from January 1989 thru January 1991 w/o finding a single peep about internal grayscale. Until that point they appear to have been selling inexpensive, unaccelerated SE/30 PDS cards for external 640x480 and 1024x768 displays alongside a lineup of NuBus cards so uninspiring as to be entirely missing from LEM's NuBus Video Card page. Micron started advertising Xceed Memory Upgrade Kits in the MacUser August 1989 issue and began advertising VidCards in the November issue of that year. Things stayed pretty much the same until they listed a NuBus Card capable of 1152x870 in their November 1990 MacUser ad.

 

It'll be interesting to find the SE/30 Internal Grayscale announcement or a review of any of their cards.

 

BTW, it would seem Micron is still rolling right along in the memory business out in Boise. Crucial is one of their trade names. I wonder if anyone has been working there for thirty-odd years?

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Can anyone take and post some really high resolution pics of both sides of the Micron Xceed 306, please?

 

It doesn't support internal grayscale. In stock form, the only resolution it supports is 640 x 480 with 8-bit on an external monitor using Sync on Green. It appears that much of the work has been done to reverse engineer this particular card. Tweaking it so as to create an internal grayscale only card appears to be a real possibility. Dunno, but it's definitely an approach to explore.

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I'm following this thread and have nothing of value to add given my complete lack of electrical engineering / programming skills, but I can definitely say that I'd happily help fund a project along these lines, in whatever format that makes sense (chipping in to help cover development costs, pre-ordering a couple kits, etc.). Having a greyscale SE/30 would be awesome. If there was a "stretch goal" to incorporate Ethernet too, I'd be super excited and willing to pay an additional amount that is probably unreasonable LOL. My current "main" SE/30 has an Ethernet card installed and I'd hate to lose that... but I agree with all the comments above about needing to avoid 'feature creep.' I don't want or need an external monitor, a CPU upgrade would be cool but is almost certainly unrealistic, etc.

 

Carry on - I'll be cheering from the sidelines!

 

Huxley

 

Edited by Huxley

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@pcamen thanks so much for those great pics. As you can see, there's no ASIC on board, it consists of discrete components. Getting one of these cards into the hands of one of out resident boffins for schematic development will be the first hurdle. Translating that into a set of modern components the equations of which are easily tweaked along with a crystal swap(?) will allow the techies to fiddle with it until it speaks A/B and Grayscale Neck Board.

 

On 10/17/2019 at 3:20 PM, ktkm said:

Yes! And accelerated graphics would be great! I would back an SE/30 Xceed greyscale adapter cloning project. :-) 

Not sure QuickDraw acceleration is needed so much on a PDS card at these resolutions. Other than the Pivot Cards, which aren't spec'd, my SuperMac ColorCard SE/30 is the only 030 PDS card listed as accelerated on LEM.

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I haven't been able to upload attachments for several days. I get a: There was a problem processing the uploaded file, -200 error every time, so here's a link to a 306-48 pic on eBay:

 

s-l1600.jpg

 

It consists of VRAM, EPROM, 74ALS series logic, GALs, Oscillator Cans and a RAMDAC. NO ASIC! [:D]
AM81C471-35JC

 

edit: links from the 'Bay aren't working either, at least not that one. Gotta click on it.

Edited by Trash80toHP_Mini

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Dunno offhand, there's not a lotta info out there. If the pics you posted are of your card, it clearly says 306-48.

 

Micron seems to have spent ZERO money advertising SE/30 VidCards of any sort. The only ads I found casually mentioned them along with the NuBus Cards, which wasn't much to begin with. They spent their advert money on the IIci Cache Card and JPEG Compression Card. I'd post a pic of the article if I could to put it into perspective. MacUser editorial content regarding Micron's Color30/Gray-Scale 30 Kit amounts to this reportage:

 

Micron Technology ([800] 642-7661] has also introduced three budget cards: one for NuBus machines and two for the SE/30. The XCEED MacroColor II ($569) is a 24bit card designed for 640-x-480-pixel displays. The XCEED Color 30 ($339) is an SE/30 PDS card that can render 8-bit color or gray scale on 640-x-480-and 640-x-870-pixel displays. The XCEED Gray-Scale 30 ($89) is a video adapter card for the SE/30 that, when it's installed in conjunction with the Color 30, turns the SE/30's internal display into an 8-bit gray-scale display.

 

MacUser October 1991  55

 

We think these things are a big deal today, but not a lotta hoopla about them back when it would seem. Gotta pull my MacWorld Archive backup from the NetBook over here to search it. I wonder if anyone made a big deal of it in the day? In April 1992 MacUser made a bit of a thing about external display cards for PowerBooks like Envisio's for my PowerBook 100. But no other mention of Micon's boards for the SE/30 at all from the October 1991 announcement through December 1992 in my search for "xceed."

 

It's amazing how little these things cost when new. Definitely budget cards as described.

 

 

 

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Best price I found was MacConnection's Feb. 1992 ad: $279 Color30 + $75 Gray-Scale30 = $354 which doesn't seem like a whole lot when compared to 24-bit, QuickDraw accelerated NuBus Cards for 21" Displays.

 

3-4x that low quote doesn't sound all that outlandish to me now, given the incredible demand. MacConnection's asking price would be $706 today. Dunno what folks think they're looking at in buying a clone, but for sure 50-60 bucks has gotta be a badly lowballed estimate the way I see it.

Edited by Trash80toHP_Mini

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While I agree with you, I wouldn't be willing to pay $700 for a clone card with no out of production parts in it. :) 

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Well the $80 was just for the yoke, not the PDS card itself, the way they worded it. Confusing though that they call it out as if it was a completely different PDS card. Probably because the lay user would've taken it in to get in pro installed?

 

I'm also of the mind that if there's a way to replicate the design without resorting to NOS components, that might be the more economical solution.

 

Where are we at as far as initial development costs (rough estimate)? Would we need to shell out the $500-$800 (not to mention sacrifice someone's Color30)?

 

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10 hours ago, Trash80toHP_Mini said:

Dunno offhand, there's not a lotta info out there. If the pics you posted are of your card, it clearly says 306-48.

Yea I got mixed up between my card and my greyscale 30 card.

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Can anyone clarify whether the analysis of the greyscale card to understand it well enough to reproduce some or all of it will be a destructive one or not? 

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